The present invention relates to a process for contacting fluids with a solid in a series of two or more packed beds with the capability for recycling the effluent of each bed individually to the inlet of that bed. More specifically, the invention is directed to achieving the advantages of a stirred slurry reactor, well known to those skilled in the art, while overcoming the solids handling problem of that type of reactor by approaching its performance with a fixed-bed recycling system. The invention relates to solid catalyst alkylation processes wherein two fluids (liquids or gases), are contacted with a solid catalyst to effect a desired reaction.
Well known in the prior art are processes which embody using a solid catalyst in a stirred slurry-type reactor either singly or in series. These reactors have several disadvantages, one being the solid handling problems when the catalyst requires regeneration. The present invention relates to a fixed bed reactor system that eliminates most of the solids handling problems but has the same advantages as slurry reactors in series. Fixed bed reactors, however, have their own inherent problems, one of which is uncontrolled heat build-up and "hot-spotting" at one or more points in the system. This can result not only in loss of product yield, but can also quickly destroy catalytic activity. Although fixed-bed reactors are well known in the prior art, a process adapting this type of reactor for individual recycle capability to effect the type of reacting usually done in stirred tank reactors has previously been unexplored.